大展弦比复合材料机翼非线性气动弹性特征与颤振研究

项目名称： 大展弦比复合材料机翼非线性气动弹性特征与颤振研究

项目编号： No.11472089

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 数理科学和化学

项目作者： 曹登庆

作者单位： 哈尔滨工业大学

项目金额： 88万元

中文摘要： 针对大飞机大展弦比机翼结构重量轻、柔性大，在气动载荷作用下会产生显著的弯曲和扭转变形，并呈现出明显的几何非线性特征的问题，开展大展弦比复合材料机翼非线性气动弹性特征与颤振研究。综合考虑结构几何非线性、气动非线性和材料各向异性对机翼运动状态的影响，将复合材料机翼考虑成变截面细长梁，建立其弯扭耦合振动的非线性动力学模型；气动力则采用ONERA-Edlin模型，其线性部分可以近似成非定常的Theodorsen模型。在此基础上，寻求简捷有效的方法以求解机翼的静平衡位置，并进行实验验证；采用小扰动分析的方法得到机翼在平衡位置附近的振动方程，研究其固有振动特性，并进行相关的模态试验；在固有特性分析的基础上，预测机翼的颤振失稳速度和非线性颤振失稳边界，研究颤振失稳后的极限环振动及其分岔等问题为大。取得的成果将为大飞机的结构与气动设计提供技术支持。

中文关键词： 大展弦比；机翼；非线性振动；颤振；分岔

英文摘要： For a wide-bodied airplane, its high-aspect ratio wing is a light-weight flexible structure that undergoes large deflection and torsion under aerodynamic force, and the deflection and torsion of the wing presents nonlinear characteristic obviously. This project is focused on the investigation of nonlinear aero-elastic property and flutter of the high-aspect ratio composite wing. Integrated into account the geometrical nonlinearity of the structure, the aerodynamic nonlinearity and the material anisotropy, the nonlinear dynamical model for coupling vibrations of a torsional and flexible beam is established for the high-aspect composite wing which is considered to be a slender cantilever beam with variable cross-sections. The aerodynamic force is formulated by the ONERA-Edlin model, the linear part of which can be approximated as the model from Theodorsen unsteady aerodynamic theory. According to the static equations of the high-aspect ratio wing, a simple and effective approach is developed to solve the static equilibrium position of the wing, and the corresponding experiments will be conducted. The perturbation method is adopted to set the vibration equations of the wing nearby the equilibrium position, and the natural vibration property is investigated and its relevant modal experiment is conducted accordingly. Based on the natural property analysis, the modern nonlinear dynamic theory is employed to predict the flutter speed of instability and the nonlinear flutter boundaries of instability, and to study the limit cycle vibration after the flutter instability and its bifurcation problem. The achievements acquired here may provide basis for the design of structure and aerodynamic configuration of the high-aspect ratio wing for the large wide-bodied airplane.

英文关键词： high-aspect ratio;wing;nonlinear vibration;flutter;bifurcation